Mental Grammar and Implicit Learning

Dezso Nemeth
Brain and Language Lab
Department of Neuroscience
Georgetown University, Washington DC 

and 

Department of Psychology
University of Szeged
Hungary

Numerous theories claim that the motor and procedural systems are the
cognitive background of mental grammar and sentence processing. The
main purpose of this research is to study the relationship between
implicit learning and sentence processing, and the role of sub-
cortical brain regions. The talk presents two studies. In a dual-task
experiment the healthy subjects’ implicit learning was measured by a
serial reaction time task, and at the same time subjects were tested
on sentence processing, word processing, and mathematical tasks.
Results show that implicit learning is significantly worse when the
parallel task was sentence processing than when it was controls. The
implication of the results is that there is relationship between
implicit learning and sentence processing, more precisely the
operation of mental grammar.

In the second study production of morphology, implicit learning, and
working memory abilities were measured of Huntington’s disease
patients. The main results show that the production of morphology is
impaired in the early stage of this disease, and 3 subjects have
difficulties with morphology prior to diagnose HD.